The steep gradient and extensive bush of the escarpment is paradise for mountain bikers. BEN LANGFORD ventures into the wild hills, hot on the trail of the enthusiastic riders who want to make the most of the environment.

Look up at the Illawarra Escarpment one sunny Saturday morning and you won't see hundreds of people engaging in some good clean fun.

Not because they're not there, but because they play underneath the canopy, on tracks too steep for walkers, in the scattered light of the dry sclerophyll forest, in near silence.

There's another world up there, one which is rarely seen by people not involved in the dirt-and-wheels sport of mountain biking.

On weekends the downhill riders start early, meeting up with friends, racing off into the bush, trying to pack in as much action as they can on the descent. Sometimes beards or tattoos poke out from under their full-face helmets and logo-adorned protective gear.

For those who don't go for high jumps, there are loop tracks, and while the pace is slower, any bush trail can bring surprises: a lyrebird, a fallen log, a face full of spiderweb. These are the largest group, the cross-country riders, usually 30 or older, without the motocross-influenced team gear, but adept at negotiating a tricky track.

The hardest of the core are the free riders, who seek out purpose-built tracks for stunts, and aspire to complicated flips, steep angles, and sponsorship from energy drink teams.

Mountain bikers generally prefer the call of a bird to the screech of a trailbike. They range from teenagers to over 60s, they have a strong community, are active online, will travel to find a good trail, and their number is growing. But here, their venues aren't, ahem, entirely legal.

Matthew Gregory of Figtree, left, and Buzz Tilley of North Wollongong ride through bushland in the escarpment at Mount Keira. Picture: ANDY ZAKELI

Topographically, the Illawarra is ideal for downhill riding. Its trails attract riders from Sydney and Canberra, and locals, with trails around Helensburgh, the Dharawal Recreation Area, Rixon's Pass below Brokers Nose, the Bulli Pass to Tarrawanna track, the bush above Thirroul, Blackbutt Forest at Shellharbour, and myriad tracks around Mount Keira.

"There's a network of riding trails that I'm aware of that runs all the way from Helensburgh to Robertson," said the Wollongong Mountain Bike Club's Scott Carson.

"There's an extensive trail network up around the escarpment but unfortunately they're ... not exactly sanctioned."

Riders dodge and slice through a mix of private ownership, water catchment land and conservation area.

But basically, it's not legal. Water catchment land is off limits, at threat of large fines. And while moves have been afoot to allow hunting in NSW national parks, mountain bikers do not enjoy the same lobbying influence.

The Appin trail, popular with riders from the Illawarra and Sydney, closed after the Tharawal local Aboriginal land council called a halt to riding on their land in 2012. Citing environmental concerns, the land council said riding would be considered trespass, as with any other private property.

But private property has often been fair game. Conflict over access is now brewing in the bush between Austinmer and Thirroul, where downhill riders race through the old Excelsior coalmine land between Foothills Road and Sea Foam Avenue.

The land has been free for decades and riders have made the most of it, carving a path that needs to be seen to be believed. There are ramps too steep to walk down, berms and embankments built around corners, and a series of large jumps that would be the envy of riders anywhere. The effort required has been significant and sustained.

Buzz Tilley is one of many riders who make the most of bush trails at the weekend. Picture: ANDY ZAKELI

The land is now owned by the Big Fat Smile childcare group, which has dented the smile on mountain bikers' faces by erecting signs warning it is an abandoned mine site, private property, no entry. Big Fat Smile said it's because of the safety risk, with unstable ground in the area. Riders continue unfazed.

Whether the signs will be obeyed, or enforced, is uncertain. But they illustrate a grapple over the use of land that is being played out at sites across the region, and preventing the Illawarra from unlocking a tourism attraction that could rival any we have.

The NSW Office of Environment and Heritage, on its Illawarra Escarpment webpage, encourages people to cycle on bush trails: "a great way to experience the remarkable diversity of nature and magnificent landscapes found in parks". But in the entire Illawarra Escarpment State Conservation Area, there's only one track where cycling is allowed - the Lower Escarpment Trail from Bulli Pass to Tarrawanna.

Elsewhere, bikes are banned for environmental and safety reasons. Escarpment soil is easily eroded and tracks are not made to handle wheels. The potential for serious accidents between walkers and riders is significant.

For bushwalkers, the thought of a near-silent vehicle speeding round a corner and wiping out their children, or leaping over a track at head height, is not a comforting one. But nor are the large dogs that walkers encounter on escarpment tracks, or the trail bikes that burn through in the evening.

Dogs, motorbikes and littering are banned. It's the bush, and enforcement is far away.

That bush is also an ideal training ground. Mountain biking became an Olympic sport in 1996, with the cross-country version making its debut in Atlanta. Carson guesses the Illawarra has produced about 20 young riders who are competing in national or international championships.

Matthew Gregory on a ride at Mount Keira. Picture: ANDY ZAKELI

Kyle Ward is racing on the world circuit in Spain, his brother Jayden is off to Norway in September for a world championship event, Carson's son Callum is in Cairns with the Australian national team, Alec Reid recently competed in the world championships there, Josh Carlson rides for the Giant endure team on the world factory circuit.

Carson, who at 51 says he is not among the oldest cohort of riders - "there's riders in their 60s, lots in their 50s", sees huge tourism potential in mountain biking.

Participants are devoted.

"There's several different events that could be held here," he said.

"Downhill events, cross-country events, and endure.

"There's a longer term, eight-hour relay race, which attracts 300-400 people. There'd be one of those held probably once a month, within driving distance of here.

"The problem event organisers have is there aren't trails near suitable accommodation areas.

"That's why we could have an advantage."

The proposal for a Mount Keira "adventure park", put forward by Destination Wollongong last month, includes a mountain bike park, catering to serious riders and families, with the potential for a cable car or gondola to return riders to the top. About 80 hectares would be needed for the park, which could host events every two weeks.

"The natural bushland environment is part of the enjoyment of riding a mountain bike."

Destination Wollongong general manager Mark Sleigh said mountain biking has a huge upside as a tourist attraction, as little infrastructure is needed, and riders help maintain the track themselves.

"From an events perspective, with our relative location between Canberra and Sydney, mountain bike events could be anything for Wollongong," he said.

"The mountain bike fraternity are extremely passionate about protecting the natural environment, and enjoying the natural environment."

One city that has made itself into a mountain biking centre is Rotorua in New Zealand, which attracts visitors from Australia. Estimates vary as to the value of the tourism to Rotorua, but are above $6 million for the local economy each year.

Wollongong City Council, appearing to grasp the potential, has promised "further investigations" of mountain biking in its recent bike strategy. It has also done a report on a regional mountain bike park. But the proposed location for the park - Cringila hills - has the space, but not the bush environment riders want.

"The trail is great, but it's not the bushland location," said Carson. "The outlook is basically industrial. [The bush] is a huge part of the appeal."

The club has had some success with Shellharbour City Council, but a proposal to use Blackbutt Forest must go through a plan of management, then a development application process. While it might suit cross-country riders, it's not steep.

A private development near the base of Macquarie Pass has potential for downhillers, with a landowner developing a free-riding park there.

In the meantime, driven by a do-it-yourself ethos and buoyed by a feeling that they're onto something brilliant, mountain bikers will continue to make the most of the grey areas.

"We've been riding, since I've been involved, about 15 years," Carson said. "We've never had an issue with any of the landowners. I don't think they sanction it, however the nature of the sport is to not really go and wreck the escarpment - you enjoy it being around you.

"The trails up there have been well maintained. Mount Keira is fantastic, some of the tracks up around there. And they're probably less obtrusive than walking trails.

"[Riders] are probably a little bit more conscious of the environment that they're riding in. The natural bushland environment is part of the enjoyment of riding a mountain bike."